At about 3:29 a.m., police received a report of a stabbing near the intersection of 26th and Folsom streets, about one block from Garfield Square.
Upon arrival at the scene, police found a male adult with a stab wound to his abdomen.
The victim was transported to San Francisco General Hospital in serious condition, police said.
Further police investigation revealed that the victim was walking alone when two unknown male suspects approached him.
According to police, the suspects asked the victim if he had any gang affiliations and when the victim told them he had none, one of the suspects brandished a knife and stabbed the victim.
The stabbing occurred about one hour after a victim was stabbed near the intersection of 17th and Mission streets, according to police.
At about 2:20 a.m. police received a report of a fight amongst a group of people in the 2100 block of Mission Street, about one block from the 16th Street Bart station.
Upon arrival at the scene, police located a man in his 30s suffering from at least one stab wound.
The victim was transported with to San Francisco General Hospital, police said.
According to San Francisco police and fire officials, two additional subjects were transported by ambulance from the scene to San Francisco General Hospital.
The extent of their injuries has not been released.
No suspects are in custody and no suspect descriptions have been released in connection with either stabbing incident as of this morning, according to police.
Police said the two stabbing incidents do not appear to be related.
Anyone who witnessed either incident is encouraged to contact the San Francisco Police Department.